Displaying items by tag: US
US: Hawaii’s Department of Transportation plans to use carbon-injected concrete for its new projects. This will include a new structure to protect a highway tunnel from rockfalls, according to Reuters. The Department of Transportation was testing CO2-injected concrete on an access road project with CarbonCure Technologies in May 2019. The latest decision follows a resolution by state legislators that city administrators ‘consider’ using CO2-injected concrete in city and county infrastructure where concrete is used.
In late June 2019 CarbonCure announced that its had formed a partnership with HC&D Ready Mix, a local concrete producer, to use its CO2-injected concrete process. It is the second deal with a concrete producer in the state that CarbonCure has arranged.
Mississippi Lime to buy Southern Lime
09 July 2019US: Mississippi Lime Company has executed a definitive agreement to acquire Southern Lime, the lime business of Covia based in Calera, Alabama. No value for the transaction has been disclosed. The deal is also subject to regulatory approval.
Southern Lime supplies high-calcium quicklime and hydrated lime products to customers in the Southeastern US, and across a range of end uses and applications. The Calera operation will increase Mississippi Lime’s production facilities to nine locations, supported by a network of distribution sites throughout the country. The business will be fully integrated into existing Mississippi Lime operations.
Turkish cement industry to focus on exports
05 July 2019Turkey: Turkish Cement Manufacturers’ Association (TÇMB) chairman Nihat Özdemir says that the local industry needs to focus on exports rather than for local consumption. He made the comments at a meeting between the TÇMB and the Cement Industry Employers' Association (ÇEİS) hosted by Deloitte, according to the Dünya newspaper. Exports grew by 46% year-on-year in the first half of 2019 to a value of US$444m driven by deliveries to the US, Ghana and Israel. ÇEİS chairman Suat Çalbıyık called on the Turkish State Railway company to abolish its fixed tariff for goods moved up to 150km to further support the industry.
TÇMB data shows that local consumption fell by 24% year-on-year to 5.12Mt in the first quarter of 2019 from 6.74Mt in 2018. Domestic sales fell by 34% to 3.98Mt from 5.99Mt. Exports rose by 37% to 0.94Mt from 0.68Mt. Local decline in the market has been blamed on a weak housing market and a slowdown in the Turkish economy.
Natural pozzolan use in the US
03 July 2019Charah Solutions has been steadily building up its fly ash distribution business in recent years with an eye on the supplementary cementitious materials (SCM) market. This week it opened the third of its new series of SCM grinding plants, at Oxnard in California, US. The unit sticks out because it is focusing on grinding natural pozzolans. The plant will receive natural pozzolan by truck and rail and then use Charah’s patented grinding technology to produce pozzolan marketed under its MultiPozz brand. The previous plants in this series mentioned natural pozzolans but this is the first to promote it explicitly.
The change is potentially telling because global demand for granulated blast furnace slag (GBFS) outstrips supply. Both performance benefits and environmental regulations are pushing this. It’s a similar situation for fly ash, also driven by trends to close coal-fired power stations in some countries. As Charles Zeynel of SCM trading firm ZAG International explained in the March 2019 issue of Global Cement Magazine, “...volcanic pozzolans are a potential SCM of the future. This is gaining traction, but it’s slow progress at the moment. This will be the answer for some users in some locations.”
The problem though is that natural pozzolans are down the list of preferred SCMs for their chemical properties after silica fume, GBFS and fly ash. The first is expensive but the latter two were traditionally cheap and easy to obtain if a cement or concrete producer had access to a source or a distribution network. Natural pozzolans are very much subject to variations in availability.
It’s no surprise then that Charah is promoting natural pozzolans in a Californian plant given that state’s environmental stance. It’s unclear where Charah is sourcing their pozzolan from but they are not the only company thinking about this in the US. Sunrise Resources, for example, is working on the environmental permits for a natural pozzolan mine near Tonopah in Nevada. As it described in its company presentation, California and Nevada are the most affected states in the fly ash supply crisis because they are, “...at the end of the line when it comes to rail deliveries from power stations in central and eastern USA.” It also estimated that California used 0.9Mt of pozzolan in its cement production of which about 90% is fly ash. The state produced 9.6Mt in 2015. Other companies are also mining and distributing natural pozzolans in the US as the website for the National Pozzolan Association (NPA) lists. Although, if this line-up is comprehensive, then the field is still fairly select. Most of these companies are based in the west of the country.
One last thing to consider is that various groups are tackling a potential future lack of SCMs for the cement industry by making their own pozzolanic materials through the use of calcined clay. These groups include the Swiss-government backed LC3 project and Cementir’s Futurecem products. Using clay should bypass the supply issues with natural pozzolans but the cost of calcining it requires at the very least an investment to get started.
As concrete enthusiasts often point out, a variant of pozzolanic concrete was used by the Romans to build many of their iconic structures, some of which survive to the present day. To give the last word to the NPA, “What is old is new again: natural pozzolan is back!” If environmental trends continue and steel and coal plants continue to be shut then it might just be right.
US: Researchers from CalPortland have published a peer-reviewed study looking at the absorption or carbonation of CO2 by buildings, pavements and structures made from concrete. The authors argue that this negative effect on CO2 emissions is not being considered in global, national and regional greenhouse gas accounting methods. The paper calls for focused studies on CO2 uptake in concrete within the context of its overall Life Cycle Assessment (LCA).
“It is time to further examine the value of concrete in the built environment as a significant carbon sink,” said Allen Hamblen, president and chief executive officer (CEO) of CalPortland. “To do so accurately, we must specifically look at the net effects of CO2 sequestration in concrete and evaluate all structures over their lifetime within a circular economy.”
The study looks at previous attempts to quantify the effect of concrete carbonation, notably using work by the Swedish Environmental Research Institute (SERI) that examined data from several European countries to develop practical models to gauge the extent of CO2 uptake by concrete globally in the built environment. Different models estimated that 15 - 20% of CO2 emissions from clinker production were reabsorbed over the lifetime of concrete structures.
US: Charah Solutions plans to open a grinding plant to make supplementary cementitious materials (SCM) from natural pozzolan at Oxnard in California. The unit will be accessible by truck and railway. It will sell pozzolan and other materials to concrete product manufacturers throughout south California.
The Oxnard plant will be operated in partnership with Diversified Minerals, a supplier and manufacturer of standard and custom blend cement and concrete products. It will receive natural pozzolan by truck and rail and then grind pozzolan marketed under the brand MultiPozz pozzolan. MultiPozz pozzolan will be distributed throughout Charah Solutions’ MultiSource materials network of more than 40 nationwide in the US with international sourcing and distribution.
“Fly ash is becoming more difficult to source in California, which is forcing the construction industry to look for viable alternatives. Natural pozzolan and other SCMs that meet ASTM specifications are generating very high interest. With Charah Solutions’ resources and DMI’s strategic partnership with the only active pozzolan mine in Southern California, we are both the closest and the first to bring these products to market,” said Jim Price, chief executive officer (CEO) of Diversified Minerals.
Cemex Colombia accused of making donation to presidential campaign in return for favours
27 June 2019Colombia: Cemex Colombia has been accused by the news division of Caracol Televisión of allegedly making payments to the Juan Manuel Santos presidential campaign in 2014 in return for preferential treatment on construction contracts. Santos subsequently won the 2014 presidential election and served until 2018.
Sources, quoted by Noticias Caracol from a US police investigation into the company, say that it paid US$1m in cash and contributed cement to local candidates. They say that the local candidates then sold the donated cement at a discount for additional campaign funds. The Office of the Attorney General of Colombia is also investigating the matter. The report by Noticias Caracol follows an expose by Semana magazine.
US: ABB has launched its Dodge Safety Mount spherical roller bearings product with a built-in patented locking mechanism. It says that this new feature can reduce installation time by up to 75% compared to traditional products. It is mounted by tightening fasteners, instead of using a hammer and other tools. The new system also allows for simple installation and removal from the same side of the bearing. The new bearing is intended for bulk material and air handling applications.
Safety Mount bearings feature a triple-lip contact seal and corrosion-resistant flinger sealing system, which prevents contamination from entering the product during installation and operation. A labyrinth seal option is available for high-speed and high-temperature applications. The product can also be used with ABB Ability Smart Sensor.
Loma Negra challenges US legal case
21 June 2019Argentina: Loma Negra is challenging a proposed US-based court case on behalf of US-based shareholders. The legal challenge alleges that the cement producer misled investors by misrepresenting its exposure to a corruption scandal and downplayed the potential impact of the economic crisis in 2018, according to the Ámbito Financiero newspaper. Loma Negra says that it was never involved in any bidding process related to the corruption case relating to its Brazilian owner Camargo Correa. The US lawsuit is also taking legal action against the banks involved with Loma Negra’s initial public offering (IPO) in late 2017.
US: Cemex has announced that it is supplying concrete, including a specialised self-consolidating mix, along with thousands of tonnes of aggregates for the replacement of the Sixth Street Viaduct Bridge in Los Angeles, California. The original 915m-long bridge, which has served as a backdrop in numerous films, was built in 1932 and is in need of replacement.
Cemex will supply 34,400m3 of ready-mix concrete. This will include 4800m3 of Evolution, Cemex’s range of self-consolidating concrete product that, in this instance, was tailored to fit the bridge’s design and the requirements of the client, CalTrans. Cemex will also supply a fibre-reinforced concrete solution for the bridge deck and structure itself. The US$482m structure, funded by a mixture of state and Federal funds, is expected to open in late 2020.